IntroductionThe act of providing analgesia is often overlooked when planning and managing a mass casualty incident (MCI). In the most recent version of the Major Incident Medical Management and Support manual, analgesia is referred to only 7 times (out of 216 pages), and no details are given concerning the modalities of pain control in the mass casualty setting. In the early stages of such events, the limited resources of emergency services and the great number of casualties mean that the scope of action of emergency personnel is usually limited to triage and providing essential life-saving interventions. Until now, analgesia has been deemed low-priority and reserved for later stages of management when resources become more abundant. New, easy, and safe ways of providing quality analgesia have shown promising results and may bridge the gap in allowing analgesia to be provided earlier in MCIs without needlessly consuming time or personnel, all the while increasing the quality of care to patients.The Major Incident Medical Management and Support principles define a major incident as an “incident where the location, number, severity or type of live casualties requires extraordinary resources.” Recent events, such as the 2015 Paris attacks or the 2017 Manchester Arena bombing, have reminded us that planning and training for these situations are of paramount importance.2Hirsch M. Carli P. Nizard R. Riou B. Baroudjian B. Baubet T. et al.The medical response to multisite terrorist attacks in Paris. When attending and managing these types of events, the main goal has always been to do the most for the greatest number, which means identifying critical yet salvageable patients through triage and delivering life-saving interventions.3Vassallo J. Smith J.E. Bruijns S.R. Wallis L.A. Major incident triage: a consensus based definition of the essential life-saving interventions during the definitive care phase of a major incident. However, there has also been some criticism of the way we anticipate and prepare for these events. Current guidelines suggest implementing a robust command-and-control structure in major incidents, while some authors suggest that the way forward is by “supporting and facilitating” autonomous frontline teams.4Mass casualty medicine: time for a 21st century refresh. Another suggestion for change in current practice has been that patients with minor injuries and expectant patients should also benefit from a portion of initially available care without having to wait until all critical cases have been managed and evacuated.5Mass casualty triage—the greatest good for the greatest number?.There is, to our knowledge, no existing literature on the experience, satisfaction, and/or expectations of major incident survivors concerning analgesia on the incident site. However, there is lots of evidence to suggest that poor pain management is commonplace in trauma victims, even in resource-rich prehospital settings with a high provider-to-patient ratio.6Oberholzer N. Kaserer A. Albrecht R. Seifert B. Tissi M. Spahn D.R. et al.Factors influencing quality of pain management in a physician staffed Helicopter Emergency Medical Service.,7Albrecht E. Taffe P. Yersin B. Schoettker P. Decosterd I. Hugli O. Undertreatment of acute pain (oligoanalgesia) and medical practice variation in prehospital analgesia of adult trauma patients: a 10 yr retrospective study. Furthermore, certain population groups are particularly affected by oligoanalgesia in trauma (women, patients of color, elderly patients).8Bradford J.M. Cardenas T. Edwards A. Norman T. Teixeira P.G. Trust M.D. et al.Racial and ethnic disparity in prehospital pain management for trauma patients. Poor management of acute pain may lead to the development of chronic pain and posttraumatic stress disorder.9Kim S.Y. Buckenmaier III, C.C. Howe E. Choi K. Sublingual sufentanil may reduce risk for psychiatric sequalae and chronic pain following combat trauma: editorial for the newest battlefield opioid, sublingual sufentanil., 10Schreiber S. Galai-Gat T. Uncontrolled pain following physical injury as the core-trauma in post-traumatic stress disorder., 11Acute pain in the trauma patient. By contrast, early and effective analgesia, apart from its humanitarian value, can help with reducing anxiety and assist with evacuation and splinting. Victims have testified about agonizing pain during evacuation and transport in mass casualty situations, and advances should be made to prevent these situations from happening.12Manchester Arena Inquiry. Volume 2: emergency response.The military prehospital environment is a low-resource, high-acuity setting that could, to a certain extent and in certain situations, resemble a mass casualty setting.13Battlefield analgesia in tactical combat casualty care. To allow for effective analgesia in the field, the military has turned away from traditional ways to deliver analgesia, such as intravenous (IV) morphine, which requires cannulation and titration, and moved toward use of other means of analgesia, such as fentanyl lozenges.14Butler F.K. Kotwal R.S. Buckenmaier C.C. Edgar E.P. O’Connor K.C. Montgomery H.R. et al.A triple-option analgesia plan for tactical combat casualty care: TCCC guidelines change 13-04. More recently, some civilian Helicopter Emergency Medical Service providers have also added these to their inventory, with positive results and an excellent safety profile.15Carenzo L. McDonald A. Grier G. Pre-hospital oral transmucosal fentanyl citrate for trauma analgesia: preliminary experience and implications for civilian mass casualty response.

The ideal analgesic administered in MCIs should have the following characteristics: easily administered, rapid onset, wide therapeutic index, minimal mental status alteration, and ideally not require the need for surveillance or monitoring. In this review, we do not discuss IV analgesia because cannula placement and titration of analgesics are excessively time-consuming in the early phases of an MCI. Furthermore, oral first-line analgesics, such as paracetamol and nonsteroidal anti-inflammatory drugs, will not be discussed either because, while their administration is simple and their safety profile excellent, onset of their effect is slow (usually >30 min) and their efficacy for traumatic moderate-to-severe pain is insufficient. The intramuscular (IM) route allows for easy and rapid administration of analgesics in patients without the need for an IV line. However, in patients with shock, the bioavailability of drugs administered through this route may be reduced. Morphine and ketamine are widely considered the gold standard in the treatment of moderate to severe pain in the prehospital setting. However, we will demonstrate they are not the best suited for analgesia in early MCI phases.

MorphineMorphine has existed since 1805, when it was isolated from opium by Friedrich Serturner.16The isolation of morphine by Serturner. It remains one of the most widely used analgesics for moderate-to-severe pain and represents a standard against which most potent analgesics are compared in research.17Hamilton G.R. Baskett T.F. In the arms of Morpheus the development of morphine for postoperative pain relief. It can be administered orally, subcutaneously, and via the IM and IV routes. Morphine has a slow central nervous system penetration, which results in delayed analgesic onset. The risk of respiratory depression remains a concern with the use of opiates, and morphine’s slow onset of action means that this complication may occur in a delayed fashion. For all these reasons, while morphine is extremely useful and effective when providing analgesia to one or a few patients at a time, including in the prehospital setting, it is an unsuitable candidate for mass casualty analgesia. Many other opioids have been developed or isolated, such as oxycodone, hydromorphone, hydrocodone, and codeine. They can be easily orally administered but suffer from similar limitations as morphine and, as such, are unsuitable for analgesia in MCIs.Dose

The question of the dose must be determined in advance when planning for the use of single-dose transmucosal or sublingual analgesics in the mass casualty setting. A larger dose potentially means more complications, such as respiratory depression, and lower doses might result in suboptimal pain control. There cannot be a one-size-fits-all approach. One possibility would be color-coding devices and providing different doses, such as one dose for children, one for small adults/teenagers/elders, and another for large adults. To reduce complexity, a single, low-range dose could be provided, and 2 of those could be given to larger teenagers or adults.

Conclusion

While life-saving interventions must be prioritized over analgesia, it is time we rethink the way we provide early, high-quality, safe analgesia to mass casualty victims. Providing analgesia in the early stages of an MCI cannot be simply thought of as upscaling usual prehospital analgesia. As such, traditional ways of providing analgesia with IV morphine and ketamine might be inadequate in these situations. Other ways of delivering analgesics, such as transmucosal fentanyl lozenges or inhaled methoxyflurane, might bridge the gap by allowing patients to benefit from early pain control. More recently, the release of sublingual sufentanil is an exciting development in available options for analgesia in the prehospital setting. Mass casualty events are highly traumatizing to victims, and any way we can find to alleviate the suffering of injured victims as early as possible must be a priority and planned for accordingly.